What are the chances Trump's war of words with North Korea escalates?

President Donald Trump addresses the 72nd Annual UN General Assembly in New York on September 19, 2017.

In the last two weeks, Donald Trump has been waging a war of words on two fronts — a domestic battle against NFL and NBA athletes and a foreign fight against "Little Rocket Man," North Korean leader Kim Jong-un. One war is dominating the headlines. The other carries with it a risk of a nuclear exchange.

Or does it?

If you follow Twitter at all, you were aware of a collective gasp this weekend when Trump responded to a typically bellicose North Korean speech at the U.N. with this tweet:

Days before, Kim Jong-un crafted his own personal insult for Trump, telling his people, "I will surely and definitely tame the mentally deranged U.S. dotard with fire." It seems that both leaders have decided to get personal, but — as the campus radicals are fond of saying — the personal is political, and tough words have been accompanied by tough actions.

North Korea, for its part, has detonated a purported hydrogen bomb and launched two missiles over Japan since Trump began his bellicose rhetoric. It's also threatening to detonate a nuclear weapon in the Pacific and shoot down U.S. planes that fly north — even if they're out of DPRK airspace. U.S. actions have been more restrained.

Its most aggressive recent action was a flight north, up the eastern coast of North Korea, by B1 Lancer bombers and F-15 Eagle fighters. The planes stayed in international waters, but they flew farther north than any other American plane this century.

These words and actions together raise the chances of war, and many Americans are understandably nervous, but the chances that the war of words will escalate into full-blown conflict are still relatively low.

To understand how the risk can escalate — yet the chances of war remain low — consider these three key realities:

First, North Korean leaders know that they would not only lose a war with the United States, they would also lose their regime and, quite possibly, their lives.

Second, to the extent that North Korea has any hope at all of achieving a victory, it has to strike first, achieve a degree of surprise, and find a way to deter the plannedAmerican counterattack (thus the rush for enhanced nuclear capabilities).

"It's not clear what [Trump] stands to gain with his aggressive words, and to the extent they have an effect, they seem to be backfiring."

Third, North Korea is prone to committing periodic hostile acts, such as sinking a South Korean warship, shelling a South Korean island, assassinating political rivals on foreign shores, and — years ago — even launching direct attacks on American forces in the field.

What does this all mean? So long as North Korea does not believe that we are preparing to launch an aggressive attack, they are highly likely to maintain the status quo. They're keenly aware of the first rule. If there's a war, they'll lose.

If, however, the DPRK believes the United States is preparing aggressive military action, it may well gamble on a first strike. But, given the first rule, its leaders would have to truly believe the end of their regime was at hand. Only perceived desperate times would justify desperate measures. I do not believe that Trump's rhetoric or Trump's tweets — especially unaccompanied by any major fleet or troop movements — are pushing North Korea to that kind of catastrophic choice.

But that doesn't mean risks aren't growing. It is the final reality that's most troublesome. Wars often begin through miscalculation, and it's easier to imagine a direct North Korean show of force — another shelling, for example — escalating more quickly in the current environment. It's also easier to imagine a North Korean overreaction to a perceived American threat.In other words, it's quite possible that we could essentially stumble into war.

That's the context in which Trump's rhetoric is most troubling. It's not clear what he stands to gain with his aggressive words, and to the extent they have an effect, they seem to be backfiring. There's no indication that his words are deterring the DPRK from pursuing an active ICBM force. To the contrary, they are incentivizing North Korea's rush to create deliverable intercontinental weapons. They aren't "scaring" North Korea into any sort of compliance with American wishes. Kim Jong-un is countering Trump rhetoric not just with rhetoric of his own but also with actions that frighten every American ally in the region — the kind of actions that raise tensions and increase the chance of miscalculation. Nor is there much evidence that Trump's rhetoric is triggering a Chinese response decisive enough to force the DPRK into compliance. At least not yet.

If our leaders are going to escalate risks — especially with the stakes this high — we want that escalation to be carefully calculated. Trump, thankfully, has surrounded himself with careful military advisers, but he is not making careful statements. Indeed, he is reportedly ignoring his advisers' advice. It's too much to say that he's actively courting nuclear conflict or even a second Korean War. It's not too much to say, however, that he's increasing risks without any clear reward.

Commentary by David French, a senior writer for National Review. Follow him on Twitter@DavidAFrench.

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